The performance of magnetroresistive random access memory (MRAM) continues to improve. One type of MRAM uses magnetic tunnel junction (“MTJ”) stacks which contain CoFeB/MgO/CoFeB as part of the film stack. MTJ patterning which contains a stack of mostly metal films has been limited to physical sputtering, which is limited in its ability to achieve vertical profiles. As a result, sputtering does not provide adequate results in tight pitch applications. Plasma chemistry using a chlorine containing gas typically requires high temperature because of the relatively low volatility of the metal halides. In these high temperature plasma techniques, lateral diffusion of chlorine atoms can lead to undue reaction with the metal or metal oxide in the device, which leads to degradation or destruction of the MTJ and the device. New and improved methods of creating magnetic tunnel junctions are highly desirable.